The New York Timesreports on the question of privacy through anonymity in public and how that can change as there is more constant surveillance of public spaces and retention of that surveillance data:

Information about our innocuous public acts is denser in urban areas, and can now be cheaply aggregated. Cameras and sensors, increasingly common in the urban landscape, pick up all sorts of behaviors. These are stored and categorized to draw personal conclusions — all of it, thanks to cheap electronics and cloud computing, for affordable sums. […]

On Friday, a company called LocoMobi announced it had acquired Nautical Technologies, the license plate recognition technology of a Canadian company called Apps Network Appliances. This gear sits at the entrance of a parking lot, identifying the license plates of incoming cars. That data goes to the cloud computing infrastructure of Amazon Web Services. When a car pulls out of the lot, the camera takes another picture, computers calculate how long a car was parked, and a charge is applied.

The company’s co-founder foresees tying the system to a car’s navigation system, enabling drivers to find and reserve nearby parking spots without wasteful driving. A license plate is certainly public information, and this all seems like a boon for drivers.

Eventually, however, something else happens, too.

“We can have so much fun with this,” the co-founder of LocoMobi, Barney Pell, who is also its chairman, said. “Imagine knowing that people who park here also park there – you’ve found the nearby stores, their affinities. You could advertise to them, offer personalized services, provide ‘passive loyalty’ points that welcome them back to an area.”

At that point public data has become personal information. It’s a little like the way a company called Euclid Analytics uses the pings when a smartphone looks for a Wi-Fi antenna (something that phones do as a matter of course) to track people moving through a crowded mall.

Euclid says it does not collect personally identifying information, though it could figure out a lot by examining those movements. In London, a software engineer inferred a significant amount of personal information by looking at public data about bicycle rentals. […]

Certainly, all these hacks on traditional privacy will not just be urban questions. With the coming of low-cost satellite systems, all of the Earth will be held to a mirror, in near real time, at an increasing granularity of visual, infrared and other kinds of data. And while companies may collect our public information, the Federal Trade Commission in the United States, along with regulators in other countries, is increasingly interested in how this data is used.